(More extreme variation in upper level wind speeds is an upshot of polar warming during boreal summer. The result is that risks of severe heatwaves, droughts, wildfires and floods increases as the Earth warms. Image source: Michael Mann, Penn State.)

From the study:

… our analysis of both historical model simulations and observational surface temperature data, strongly suggests that anthropogenic warming is impacting the zonal mean temperature profile in a manner conducive to wave resonance and a consequent increase in persistent weather extremes in the boreal summer.

What this means is that the new study provides still more evidence that the Jet Stream’s north to south variance is increasing during summer. As a result, it is enabling powerful heat domes to form in regions where winds run from south to north. In regions where the upper level winds run from north to south, it creates cooler zones in which powerful storms can flood large swaths of countryside. In other words, increasingly juxtapposed zones of extreme temperature anomalies and higher atmospheric instability and moisture loading tend to form more and more often. And this results in weather patterns that we have never really seen before.

(An Inconvenient Sequel is a call for action on climate change like we’ve never seen before. And the imperative to act on climate is now stronger than it ever was.)

The fact that the Mann study uses observational and model assessments to find that such changes are likely to very likely now being caused by human-forced warming and related polar amplification is a highly significant scientific finding. It adds one more attribution tie to the extreme weather events that we’ve been seeing with increasing frequency. A tie directly to global warming. And it does so through model studies that identify the underlying physical mechanisms at work. It’s a pivotal moment in the atmospheric sciences. And everyone needs to sit up and pay attention.

Credits:

Hat tip to Colorado Bob

Hat tip to Cate

Scientific hat tip to Dr Michael Mann

(Please support publicly-funded, non-special interest based science that is now under assault by the climate change denying Trump Administration)

In a record-hot world, there’s a lot of lower-latitude heat just waiting for a weakness in the increasingly feeble Jet Stream to make a big poleward rush. Such was the case today as an intense wave of warmth exploded up from the Equatorial region and began to spread summertime temperatures over sections of West Antarctica — technically still in the grips of the Southern Hemisphere’s winter season.

(A surge of heat breaks over West Antarctica on September 2nd, 2016, pushing air temperatures over vulnerable coastal glaciers and ice shelves near or above the melting point [0 degrees Celsius]. Image source: Earth Nullschool.)

The warm winds began their southward turn about a thousand miles west of coastal South American and along the 20 degrees south latitude line. Tapping hot, tropical air, the winds then ran over hundreds of miles of open ocean — following the arch of a bulging ridge in the Jet Stream. These winds then gathered, howling through the Southern Ocean with storm force gusts of 50 to 65 mph before delivering their payload of abnormal warmth to West Antarctica.

Larsen C Ice Shelf Experiencing Above-Freezing Temperatures in Winter

Along the coast of Ellsworth Land, temperatures have risen to near the thawing point (0 degrees C), in winter, in a region that typically sees -2 to -3 C readings during summer. Temperatures that are 15 to 23 C above average (27 to 40 F) now range all over the Antarctic Peninsula and nearby areas of West Antarctica. Perhaps most dramatic are the 1.5 C readings coming from sections of the C region of the Larsen Ice Shelf bordering the Weddell Sea. There, downslope hurricane-force winds howling over the shelf are helping to spike local temperatures even as sea ice in the Weddell is splintered and shoved away from the Larsen C edge.

(A wave of 20+ C [36+ F] above-average temperatures blankets the vulnerable glaciers of West Antarctica on Friday, September 2nd. This pulse of tropical warmth is enough to drive readings over Antarctica to summertime or warmer ranges during winter, with some regions that typically experience below-freezing temperatures year-round nearing or exceeding the thawing point. Image source: Climate Reanalyzer.)

(Differences between average summer and winter temperatures over Antarctica. For sections of West Antarctica near the Antarctic Peninsula, Friday through Sunday will see temperatures more typical to Antarctic summer — during late winter. Image source: European Center for Medium-Range Weather Forecasts.)

A Winter of West Antarctic Heat — Larger South Pole Warm-up on the Way?

More broadly, warming this region to above freezing for extended periods is a concern among glaciologists. In the past (during the Pliocene and Miocene), when atmospheric CO2 levels have hit a range of 390-405 parts per million or above, West Antarctica (and ultimately East Antarctica) experienced warmth which resulted in seas that were many feet and meters higher than today. With atmospheric CO2 readings likely to average near 405 ppm during 2016 (or total greenhouse gas levels in the range of 490 ppm CO2e), it appears that frequent periods of summer-like temperatures and related increasing melt pressure are now possible during polar winter.

(More severe melt stress for Antarctic glaciers? NOAA’s CFSv2 model shows a ridiculously hot South Pole summer may be on the way. Side note — over the past year or so this forecast model has run somewhat cooler than actual temperatures for the Arctic region. Image source: NOAA.)

Taking this most recent warming event into context and looking forward into late 2016 and early 2017, at least one global forecast model is predicting a period of severe Antarctic warming during this time. NOAA’s CFSv2 model, for example, finds a very extreme Antarctic temperature spike emerging over pretty much all of Antarctica during the late Southern Hemisphere summer and early fall months of 2017.

They call them rain bombs. A new breed of severe storm fueled by a record hot atmosphere. One capable of dumping 2-4 inches of rainfall an hour and generating voracious flash floods that can devour homes and cars in just minutes. And in southeast Texas, the rain bombs have been going off like gangbusters.

In this week’s most recent iteration of flaring, climate change induced, storms, a region north of Houston and south of Dallas saw flood after flood after flood. Now, hundreds of people have been forced to abandon inundated homes, thousands of cars have been submerged, and seven people are dead. Rainfall totals for the region over the past seven days have averaged between 7 and 10 inches. But local amounts in the most intense bombification zones have come in at 16, 19, and even as high as 30 inches in Washington County. All time record rainfall totals that might be associated with a powerful hurricane. Floods that would typically happen only once every 500 years. But in the new moisture-laden atmosphere of a record warm world, a garden variety thunderstorm now has enough atmospheric oomph to frequently set off what were once multi-century floods.

(Rain bombs again explode over Texas in a huge complex of storms on Tuesday afternoon in this GOES enhanced satellite shot. It’s all part of the same stormy weather pattern — associated with a trough and an upper level low — that over the past five days produced another round of record flooding over Texas. And it’s expected to remain in place through the end of this week. With more severe storms firing and 4-8 inches of additional rainfall on the way for some sections of soggy Texas, it appears that still more extreme flooding is likely. Image source: NOAA.)

In isolation, the current Texas floods would be an extreme record disaster worthy of the weather history books. But it is just one of three such severe rainfall events to strike southeastern Texas since April. And, unfortunately, more storms are on the way as a strong ridge of high pressure out west is expected to generate another deep Central US trough and related rain bomb inducing storm pattern over the next five days.

West Coast Turns up the Heat

As parts of Texas face never-before-seen flooding, the US West Coast is staring down the gullet of an extraordinary surge of heat. A gigantic blob of hot ocean water off that region of the world is feeding the growth of a powerful atmospheric wave. And once the ridge of this wave really starts to swell northward on Friday, Saturday, and Sunday, record hot temperatures are bound to explode all over the US West Coast and on up into Canada.

(Sea surface temperature anomalies on May 31, 2016. Extremely hot sea surface temperatures over a vast area stretching from the Equator to Alaska and all along the US West Coast enhance the development of strong ridges in the Jet Stream that have tended to spur extreme heatwaves over the past few years. Ocean temperatures over this zone now range between 1 and 6 C above normal late 20th Century values. Image source: Earth Nullschool.)

In Fresno, the mercury is expected to rocket to 108 degrees Fahrenheit by Saturday — or about 18 degrees above normal for early June. Sacramento is expected to see 106 F readings at the same time — which is around 20 degrees above average for that Central California location. Further north, temperatures are also expected to skyrocket with Portland predicted to strike near 98 F on Sunday and Spokane calling for 96 F. In fire-ravaged Fort McMurray, the mercury is expected to top out at 85 F on the same day.

This expansive bulge of heat is expected to cover pretty much all of Western North American. Rising from the Desert Southwest, it is predicted to run through Oregon and Washington, rise up through Canada, and touch even the shores of the rapidly thawing Arctic Ocean.

Conditions in the Context of Human Caused Climate Change

The broader conditions fueling both record rain and potential record high temperatures over the North American West are the same. A record hot global atmosphere is one that is burdened with more heat and moisture than ever before. One that will inevitably produce more extreme rainfall and heatwaves than we are used to.

Locally, additional features related to a fossil fuel based warming of the world further contribute to the problem. Over the Northwestern Pacific, sea surface temperatures ranging from 1-6 degrees Celsius above average (2 to 10 F) generate a tendency for heatwaves and strong high pressure formation. These systems have often taken in all of the US West even as they’ve extended on up into Canada and Alaska. Adding to the problem is sea ice loss over the Arctic Ocean — which as of today is seeing the lowest ice extent ever recorded for this time of year. This sea ice loss tends to aid in Arctic warming which weakens the Jet Stream, which in turn tends to meander — creating these exaggerated trough and ridge patterns that have been associated with so much extreme weather recently.

(Earth Nullschool map of Jet Stream wind pattern predicted for early June 5, 2016. A powerful ridge expected to form over the US West Coast is predicted to drive record heatwave conditions there by this weekend even as a facing trough will again spike the risk for extreme rainfall events over Southeastern Texas. This Jet Stream feature and related severe weather conditions — ranging from severe heat to floods — is now influenced by numerous effects currently emerging as human-forced climate change worsens. Image source: Earth Nullschool.)

Large, hot ridges forming in one region tend to generate deep, stormy troughs in another. And the ridge over the US West has resulted in the formation of a related trough and unsettled weather pattern over the South-Central US centering on Southeast Texas. This trough has pulled cold, unstable air into the upper levels of the atmosphere over Texas even as it fed upon an uncanny volume of moisture streaming in off the abnormally hot waters of the Gulf of Mexico and Pacific Ocean.

The results? Well, we’ve already experienced them in the form of record floods for Texas, periods of record heat for the Western US, and a never-before-seen May wildfire outbreak in Alberta, Canada. This week, the overall pattern is again expected to ramp into high gear — which is likely to produce possibly never-before seen June heat out west and more extreme flooding for Texas.

A multi-day siege of severe thunderstorms morphed into a major flash flood event in parts of Texas, Kansas, and other states late Thursday into Friday, and more severe weather is expected into Friday night. — Weather Underground.

*****

It was a stifling hot and humid day that set the scene for the Exxon shareholder meeting this week. There, in Dallas, Texas on Wednesday, oil company CEO Rex Tillerson found himself besieged by environmentalists enraged over his company’s decades-long campaign to misinform the public on climate change and by shareholders concerned about the company’s future prospects. But what the climate change denying oil company CEO, and even NOAA weather forecasters, didn’t know was that an extreme rainfall event worsened by the very smoke and fumes emitted by Exxon was starting to gather over Southeast Texas — not far from where the shareholder proceedings were taking place.

Outside the meeting, a 13 foot long ice statue spelling out the words — #ExxonKnew — rapidly melted in the sweltering heat of an atmosphere roiled by the powerful climate-altering forces fossil fuel entities like Exxon had already unleashed upon the airs of our world.

‘Siege of Storms’ Batters Texas

By Thursday, the day after Exxon’s shareholder meeting, an expansive trough had extended down from Canada and over Texas. Exploiting this hole in an increasingly weakened Jet Stream cool, Arctic airs plunged south. Crossing the Great Plains into Texas, this unstable atmospheric mass came directly into confrontation with a super-heated, moist flow rising off the Gulf of Mexico and Pacific Ocean.

(Very heavy storms firing off over Southeastern Texas have dumped record amounts of rainfall over portions of the state and set off a flash flood emergency. Image source: NOAA.)

Both the big Jet Stream dip and the extreme moisture content in the airs over Texas were not normal. Both were new features enabled by a human-forced (Exxon-forced) warming of the world. For with global temperatures early this year spiking to 1.4 C above 1880s values, the planetary atmosphere is now enabled to contain about a ten percent higher moisture load than during the late 19th Century. It’s a weird new atmosphere that is now capable of producing storms with previously unimaginable heights of 70,000 feet over temperate Latitudes. And as the current El Nino fades and a temporary 0.2 to 0.4 C dip in global temperatures takes place in the cyclical transition to La Nina, some of that added, unprecedented excess of atmospheric moisture is bound to fall out in the form of never-before-seen rainfall events.

The storms resulting from what can best be described as a climate mangled by fossil fuel emissions produced rainfall of an extreme, record-shattering intensity in a region between Houston, Waco, and Austin over Thursday and on into Friday. In Brenham, 65 miles to the northwest of Houston, the 24 hour record for rainfall was shattered as 17 inches inundated local roads and communities. According to Weather Underground reports, one weather observer recorded 19.14 inches of rain after having to empty an overflowing gauge. In Bastrop County, emergency crews were overwhelmed by calls for water rescues as vehicles were rapidly submerged in the heavy flood. Now, at least one person is presumed dead and five people are missing in yet one more tragic storm and flood event sparking off in a record warm world.

Both satellite and weather radar show massive storms continuing to fire over this region. And GFS model forecasts indicate a strong likelihood for continued severe thunderstorm formation over Texas on into both Saturday and Sunday even as heavy rainfall propagates eastward over the Mississippi River Valley and Southeastern US. So this extreme event — a ‘multi-day siege of storms’ enabled by climate change — isn’t over by a long shot. A heavy punch of incessant flooding that is already prompting warnings of rivers over-topping banks all throughout and downstream of the affected region.

This most recent extreme rainfall event’s occurrence immediately following Exxon’s shareholder meeting is yet one more odd and ironic coincidence of human-caused climate change. A black irony similar to that of the Fort McMurray fires.

But perhaps even more disturbing than its coinciding with the Exxon shareholder meeting was the storm’s unpredictable nature. As noted above, a basic understanding of atmospheric physics in a warming world points toward an increasing risk of extreme rainfall events as El Nino transitions to La Nina. This risk is particularly severe in the new elongated trough patterns that have tended to form due to polar amplification and sea ice loss in the Arctic. However, current weather forecasting appears to be completely unaware of or unwilling to report on this new risk.

(The NOAA precipitation forecast issued on May 25 just before Thursday and Friday’s extreme rainfall event failed to capture any indication that a 17-19 + inch rainfall event was on the way. An indicator that warming related extreme rainfall potentials may not be fully plugged in to current forecast models. Image source: NOAA.)

To this point — NOAA weather forecasts earlier this week had identified some risk of severe rainfall over this region. But the forecasts had only predicted around 3 inches of rainfall in the most heavily affected areas. The forecast therefore undershot Thursday rainfall intensity by 14-16 inches. And this makes it look like the current weather models are having some serious difficultly keeping up with the human-forced atmospheric changes that are now fully in swing. Combine this with current weather media’s near complete blindness (there are noted exceptions — Weather Underground included) to factors related to human-caused climate change and we have what could best be described as a hazardous degree of under-reporting on climate related risk factors. And the result is a great underutilization of a vast array of weather sensors and scientific talent that would be capable of providing helpful and life-saving information if only they were enabled to. But media-wide, we’re still living and acting as if climate change doesn’t affect the weather.

As a result, pretty much everyone — drivers, emergency responders, government officials, weather forecasters — were caught off-guard by this particular storm system’s severity and the numerous flash floods that resulted. So it’s pretty clear that the language of denial that started in places like the board-rooms at Exxon has become pretty much all-pervasive. A situation that will need to change if we’re going to effectively respond to the ever-more-severe events that are surely coming down the pipe.

NASA GISS head — Gavin Schmidt — in a recent tweet estimated that 2016 would fall into a range near 1.32 C above the 1880-1899 average that NASA uses for its preindustrial baseline. By comparison, 2015 — which was the most recent hottest year on record after 2014 (three in a row!) — hit 1.07 C above the 1880-1899 average.

(According to NASA, the first three months of 2016 were 1.25 C above the NASA 20th Century baseline and a ridiculous 1.47 C above the 1880 through 1899 preindustrial average. Image source: NASA GISS.)

As a result, 2016 will likely have jumped by about a quarter of a degree Celsius in a single year. If every year from 2016 on warmed up so fast the world would surpass the dreaded 2 C mark by 2019 and rocket to about +22 C above 19th Century averages by 2100. That’s not going to happen. Why? Because natural variability assisted greenhouse gas warming from fossil fuels to kick 2016 higher in the form of a serious heavyweight El Nino. But it’s a decent exercise to show how ridiculously fast the world is expected to warm from 2015 to 2016. And in the 2014-2016 string of three record warm years in a rowwe are basically expecting a 0.40 C jump above the then record warm year of 2010. Given that the world has warmed, on average by about 0.15 C to 0.20 C per decade since the late 1970s, what we’re expecting to see is about two decades worth of warming all cram-jammed into the past three years.

More Severe Arctic Heat is on the Way

But the Earth, as of this Earth Day, hasn’t warmed evenly. A far, far greater portion of that excess heat has stooped over the Arctic. During the first three months of 2016, the Arctic region above 66 degrees North Latitude has been fully 4.5 C hotter than the NASA 20th Century baseline. That’s a departure more than three times that of the rest of the Earth. And that’s bad news for anyone concerned about sea ice, or polar bears, or Arctic carbon feedbacks, or predictable seasons, or extreme droughts and floods, or the Jet Stream, or Greenland melt, or sea level rise, or … well, you get the picture.

(Neven posted this excellent blog tracking a ferocious amount of heat in the region of the Greenland and Barents Sea. Arctic Sea Ice Forum commenter Andreas T provided this graphical representation of sea ice disintegration as it was blown into waters just to the north of Svalbard earlier this week.)

As Winter progresses into Spring, temperatures typically moderate — closing in on baseline averages. And this year has been no exception. However, readings for the entire Arctic have tended to range between 1.5 and 2.5 C above average over the past two weeks. These are some seriously hot departures for Spring. Enough to keep Arctic heat in record ranges for 2016.

Three Powerful Warm Wind Events to Strike the Arctic in Concert

But over the coming five days, a series of south-to-north warm wind events is expected to push even these seasonally excessive readings higher.

(GFS model forecasts predict Arctic temperatures to rise into a range between 3 and 5 C above normal for this time of year over the coming week. Such departures are in record ranges and will likely result in rapid snow and sea ice melt even as it drives a wedge of cold air out of the Arctic and over Europe — setting up a high risk of very severe weather events. Image source: Climate Reanalyzer.)

The first event is predicted to originate over the Yamal Peninsula of Russia during Saturday and Sunday — lasting on into Monday and Tuesday. There, temperatures are expected to rise into the (scorching for the Arctic at this time of year) mid 30s (F) as strong, warm winds blow over about 1,000 miles of western Russia and on up into the Kara and Laptev seas which are predicted to, likewise, experience near or above freezing temperatures. Over the entire region, temperatures are expected to range between 18 and 36 degrees F (10-20 C) above typical daily averages for this time of year. Snow and sea ice melt melt rates in this already rapidly thawing region will almost certainly pick up pace in the face of these obnoxiously unseasonable readings.

A second warm wind event is predicted to heat up Greenland, Baffin Bay, the mouth of Hudson Bay and a chunk of the Canadian Archipelago on Monday and Tuesday. A 1,500 mile synoptic southeast to northwest air flow is expected to originate in the Central North Atlantic. Running along the back of a high pressure system rooted between Iceland and Southeastern Greenland, these winds will ram a broad front of above-freezing airs over a rapidly melting Baffin Bay, dramatically warm the southern 2/3 of Greenland, and flush a comparable warm air pulse into the outlets of Hudson Bay. Temperatures in this broad zone are also expected to hit 18-36 F (10-20 C) above average readings. And its effects will likely be strong enough to initiate another strong early season melt spike for Greenland in addition to aiding in driving a quickening pace of melt for Baffin and Hudson bays.

(Shattered sea ice over the Beaufort and Chukchi looks as if it’s been fractured from a blow from Thor’s mythical hammer Mjolnir. Open water and very thin ice openings stretch as wide as 60 miles in some sections. A warm wind event later this week is expected to provide still more melt pressure to this already greatly weakened sea ice. Image source: LANCE MODIS.)

A final warm wind event will be fed by a big warm up across Alaska predicted to settle in on Wednesday and Thursday. There, temperatures in Central Alaska are expected to rise into the lower 60s as two stalled out lows to the south pull warmer airs up from the Pacific Ocean. This heat is expected to invade the Chukchi and Beaufort seas driving temperatures to near or above freezing over Arctic Ocean surfaces that have already witnessed a great shattering of ice and an opening of dark, heat-venting open water holes. There the anomaly spike will be slightly milder — in the range of 15-32 F (8-18 C) above average. Such heat will provide melt stress to the fractured Beaufort, likely making more permanent the wide array of open water and thin ice spaces as the push toward Summer advances.

Mangled Jet Stream to Bring Storms to Europe

As all this heat bullies its way into the Arctic, a flood of cold air is expected to flee out of the region and on down a big dip in the Jet Stream — making a late-season invasion across the North Atlantic and into Europe. There, as we’ve seen previously during recent warm wind invasions of the Arctic during Fall, Winter and Spring, warm air from the south tends to cause cold to break out and then to dive down the trough lines. And there’s a huge trough predicted to dig in over Europe.

We should expect some rather severe weather to accompany this Springtime onrush of colder air — including potentially extreme thunderstorms, flooding, and even instances of late April snowfall over parts of Norway, Sweden, Scotland, the Alps, and sections of Germany.

(A very deep Arctic trough is expected to dig into Europe and the Mediterranean this coming week bringing with it the likelihood of some very severe weather. Image source: ECMWF/Severe Weather EU.)

Likely increased rates of sea ice melt, a severe blow to record low snow packs around the Arctic and a likely freakish cold air and severe weather invasion of Europe are all a result of this extreme Arctic heat playing havoc with typical weather and seasonality. By the middle of next week, temperature anomalies for the entire Arctic may rise to as high as 5 C above the already much warmer than normal 1981 to 2010 average. In such a case, we could hardly expect weather or climate conditions to be normal and there appears to be a big helping of weirdness and extreme effects coming down the pipe over the next seven days.

Today the globe is feeling quite a bit of backlash from a human-warmed sea surface and atmosphere. As it ends up, Dr. Kevin Trenberth was right. Deep ocean warming set off by heat-trapping fossil fuel emissions and building up through the first two decades of the 21st Century did re-surge from the depths to haunt us in 2014, 2015 and 2016. In that wrenching global climate system shift to the hot side of natural variability, a titanic El Nino emerged. It was one of the top three strongest such events in the modern record. One that by NOAA’s measure appears to have tied the extreme event of 1998 at its peak intensity.

The predicted patterns and potential worse-case events (such as heatwave mass casualties, coral bleaching, and sea ice loss) were also contrasted by a number of surprises. The first and perhaps most ominous was the failure of El Nino to bust the California drought. Though the West Coast of the US did experience a number of storms, the pattern was more typical of normal Winter moisture for the Northwestern US even as drought continued throughout the Southwest. Moisture instead tended to split fire-hose fashion — with storms either cycling northward into Alaska, the Aleutians, or the Bering Sea, or south over Southern Mexico or Central America, up across the Gulf and on out into a particularly severe storm zone forming in the North Atlantic.

(Over the last 30 days the southwest drought re-emerged as a blocking pattern again began to take hold over Western North America and the Eastern Pacific. Image source: NOAA/CPC.)

This continued loss of moisture for the US Southwest despite a record El Nino is particularly apparent in the Climate Prediction Center’s most recent precipitation anomaly measure for the last 30 days. Here we find that large parts of Central and Southern California have received just 10 to 50 percent of typical rainfall for this period. Coupled with 1-3 C above average temperatures for the month, this loss of rainfall during what would typically be California’s wettest period has come as a disappointment to many who were hoping a strong El Nino would help break the state out of a crippling drought. Now, the window for late Winter and early Spring rains is starting to close even as the blocking pattern appears to be strongly re-established in both the present weather pattern and in the forecast model runs.

But perhaps the biggest surprise coming from this El Nino year was a set of weather events in the North Atlantic that were likely more related to climate change. There, severe storms hammered a flood-beleaguered UK as a greatly distorted Jet Stream heaved Equatorial heat and moisture northward — rushing it up over a ridiculously warm and apparently backed-up Gulf Stream before slamming it on into a likely Greenland ice melt-outflow related cool pool. There the heat and moisture collided with cold to produce the epic storms that then vented their fury upon the UK.

(December 29th saw temperatures rise above freezing at the North Pole — the first time temperatures have warmed so much for this high Arctic region so late in the year. Image source: Earth Nullschool.)

Though we may see these two events — the failure of El Nino to provide heavy rains to the US West Coast, and the massive northward pulses of storms, heat and moisture hitting the North Atlantic — as unrelated, the twain patterns appear to be linked to an ongoing polar amplification. Overall, heat within the Arctic has tended to weaken the Northern Hemisphere Jet Stream over these two zones. And even during El Nino, when the Jet would have typically strengthened, we have continued to see high amplitude wave patterns forming over these regions.

But as El Nino weakens and the Equator cools, the Jet Stream would tend to slow even more. Such an atmospheric state would tend to further exaggerate already significant Jet Stream wave patterns — transferring still more low-Latitude heat poleward. In addition, the ocean gyres tend to speed up as El Nino fades or transitions to La Nina. The result is an amplified pulse of warmer waters emerging from southern Latitudes and entering the Arctic.

It’s for these combined reasons — tendency to amplify south to north atmospheric heat transfer into the Arctic post El Nino and tendency to flush warmer waters toward Arctic Ocean zones during the same period that it appears we are entering a high risk time for potential new sea ice melts and possible related Greenland land ice melts during 2016 and 2017.

(Northeastern Pacific Hot Blob remains at high intensity even as its size is predicted to expand through July. Meanwhile, very warm sea surface temperatures are predicted to remain in place off the Eastern Seaboard. The net effect of these two hot blobs may be to shove the Jet Stream far northward over North America during the summer of 2016 — potentially increasing the risk of widespread and potentially record heat and drought. Predicted very warm sea surfaces in the region of the Barents and Greenland seas — in excess of 3 C above average for a large region — is also cause for concern. This is not only due to risk for sea ice loss through this zone, but also due to its potential to set off blocking pattern and heat dome formation over Eastern Europe and Western Russia. Image source: NOAA/CFS.)

El Nino to Weaken and Then Return; or is a Shift to La Nina Now Under Way?

Related to a polar and ocean warming-enhanced tendency to generate high amplitude Jet Stream waves — as well as associated persistent heatwaves, droughts, and floods — is the heat balance of the Equatorial Pacific. Strong El Ninos, or even a tendency to remain in or near an El Nino state, has historically aided in the breaking of new record global high temperatures when linking up to the greenhouse gas warming trend. Meanwhile, the shift toward La Nina has tended to enhance a range of global heating related issues including record rainfall events and large injections of heat toward the poles in the drop off from El Nino to La Nina.

The cause for increased risk of major precipitation events is due to the fact that El Nino is providing a massive moisture bleed into the atmosphere at times of peak intensity. With the current El Nino topping out near record levels and with global temperatures at above 1 C higher than 1880s averages, global atmospheric moisture levels are hitting new record highs at this time. If global temperatures subsequently drop by around 0.1 to 0.2 C during a transition into La Nina (into a range about 0.9 to 0.8 C hotter than 1880s values) then the atmosphere will be unable to keep a larger portion of that extra moisture in suspension and it will fall out as precipitation — primarily wringing out where the major trough zones tend to set up. We should be very clear here in saying that the drought risk related to a global warming intensification of ridge and heat dome formation is not reduced during such instances — just that the risk of extreme precipitation events is enhanced.

(During 2011, as the 2010 El Nino faded into La Nina conditions, a high amplitude wave in the Jet Stream set off record heat, drought and wildfires over Russia even as Pakistan was hit by a month-long deluge that was the worst rainfall event for the region in the last 1,000 years. La Nina’s tendency to wring excess water out of the atmosphere can enhance the risk for such events to occur in a warming climate state. Image source: NASA.)

As for risks to sea ice, we’ve provided some of the explanation above. However, it’s also worth noting that the mobility of heat poleward tends to be enhanced during the periods when El Nino drops off toward La Nina. During these times, Equatorial heat tends to propagate in wave fashion toward the Poles — especially toward the Northern Hemisphere Pole which has already lost its strong Jet Stream protection warding away warm air invasions.

These two factors are major issues when considering whether La Nina or an ENSO Nuetral state will appear post El Nino during 2016. But there is a third — rate of global temperature rise. Though the primary driver of global warming is a massive human fossil fuel emission, the response of the world ocean system can significantly wag the rate of atmospheric temperature increases on a decadal time scale. If the ocean tendency is for La Nina, this would tend to somewhat suppress the overall decadal rate of temperature increase — and we saw this during the 2000s. But if the ocean tendency is to produce El Ninos (in a switch to a positive Pacific Decadal Oscillation, as appears to be happening now), then the overall pace of global atmospheric temperature increase would tend to be enhanced.

( IRI/CPC consensus model runs show a drop off to a weak La Nina by late in the year. However, CFS model runs [image below] have shown a tendency to predict a resurgence of El Nino conditions by Fall. Image source: NOAA/CPC.)

To this point we find that the official model forecast consensus published by NOAA (IRI/CPC figure above) shows a transition to ENSO neutral states by May, June, and July which then proceeds on to a very weak La Nina by Fall. In such a drop off, we would likely still see record global high temperatures during the period of 2016 (in the range of 1.03 to 1.15 C above 1880s values).

However, the late 2016 and 2017 tendency for temperatures to recede from new record highs would be somewhat enhanced (likely dropping below the 1 C above 1880s mark in 2017 or 2018 before again making a challenge to the 2015-2016 record with the potential formation of a new El Nino in the 3-5 year time-frame of 2019 through 2021). It’s worth noting that this scenario shows an increased risk of a stronger warm air pulse heading toward the Northern Polar zone together with added fuel for extreme precipitation events as global temperatures would tend to drop off more swiftly from late 2015 and early 2016 peaks.

(CFSv2 model run — shows El Nino continuing on through the end of 2016. Over recent months, the CFSv2 series has shown a high accuracy. However, NOAA’s current forecast preference is for the IRI model set predictions [previous image above]. Image source: NOAA/CPC.)

In contrast, the CFSv2 model forecast from NOAA (above image) shows El Nino only weakening through to July and then re-strengthening in the October-November time-frame. This CFS model scenario would result in higher atmospheric temperatures in 2016 — practically guaranteeing a lock on an unprecedented three back-to-back-to-back record warm years for 2014, 2015, and 2016. But such a scenario — implying that the Pacific Ocean had entered a new period of El Nino tendency — would also tend to keep atmospheric temperatures nearer to the newly established record highs.

Under the CFSv2 scenario, we may expect annual average global temperatures to rise as high as 1.08 to 1.2 C above 1880s values during 2016 (a very extreme departure and one uncomfortably close to the 1.5 C warming mark). These extreme values would, perhaps, recede to around between 0.9 and 1.1 C during 2017 so long as the second El Nino pulse did not remain in place for too long. However, if the bounce back toward El Nino conditions was strong enough in late 2016, there would be an outside chance that the globe may experience not 3, but an absolutely obnoxious 4 back-to-back record warm years.

(During 2015 global annual temperature rocketed to above 1 C hotter than 1880s values. There’s at least an even chance that 2016 will be hotter still. Considering the considerable heating tendency imposed by a fossil fuel-forced warming of the world, how much worse can it get during the 21st Century’s second decade? Image source: NASA GISS.)

Meanwhile, the warm air pulse heading toward the poles may be somewhat muted under this scenario. A statement that should be qualified by the fact that we’ve already seen a substantial amount of El Nino heat heading poleward during the present event. In addition, potentially heavy rainfall events may not receive the added oomph of a decent global temperature drop to wring out more moisture. A statement that requires the further qualification that overall atmospheric moisture loading is enhanced by rising global temperatures — so comparatively less heavy rainfall is a relative term here.

(Jonas begins its ocean-heat-fueled rampage on the evening of Thursday, January 21. Image source: NOAA.)

A Warming Arctic Shoves the Cold Air Out

To understand how climate change helped make Jonas so extreme, it’s best if we start our tale in the Arctic. For if we could mark an area on the Earth’s surface that is at the very heart of impacts for human-caused climate change it would be in that zone of the far north above the 66th parallel. It is there that we see the most dramatic, most rapid changes — to ice, to weather, to the thawing lands, to life itself. But unlike what might be said of an American city made famous by its penchant for sin — what happens in the Arctic doesn’t stay in the Arctic.

And it is a massive accumulation of Arctic heat over the past few weeks that has forced Arctic temperatures, in places, to rocket to above 36 degrees Fahrenheit (20 degrees C) warmer than average. A heating up of the entire region to 2-3 degrees Celsius warmer than the already warmer than average 1979- 2000 baseline. An Arctic warm-up that muscled out a howling torrent of cold air that then raged on into a deep trough in the Jet Stream now forming over the eastern half of the United States.

(An Arctic that is, on average 2.02 C hotter than normal on Friday joins with a high amplitude wave in the Jet Stream and together drives a massive flood of cold air into eastern parts of the US on Friday. Cold air slamming head on into unprecedented heat and moisture bleeding of the Atlantic Ocean to form the historic weather event that is now in the pipe. Image source: Climate Reanalyzer.)

CAPE — Storms Fueled by Cold Colliding With Hot

In weather parlance, a trough, or a big dip in the Jet Stream is a storm generation zone. The reason has to do with the nature of how extreme differences in temperature and moisture can provide fuel for strong storms. It’s this very temperature differential that sits as the cornerstone of our current understanding of how extreme storms are fueled in terms of Convective Available Potential Energy (CAPE).

In the one case, cold air can’t hold as much water in suspension as warm air. So a big flood of cold air can often fuel major precipitation events when coming into collision with hot, moisture-laden air. As hot and cold air are sandwiched closer together, winds — at both the upper and lower levels — tend to increase in velocity. The higher the difference in temperature, the stronger the winds. When these winds run along a big dip in the Jet Stream — like the one now racing over the US East Coast — they can spin off twists and vortexes that can rapidly develop into powerful low pressure systems.

The lows then feed on the difference in temperatures between the two sides of the dividing air-mass — cold on the one side, and hot, wet on the other. The bigger the differential, the more heat and moisture on one side, and the more cold on the other side, the more potential that such low pressure centers will develop into monster storms. The more potential that the storms will develop these crazy atmospheric sandwiches of hot and cold air that really crank out the extreme weather.

(“Tremendous Vertical Motion.” Anthony Sagliani tweets about extreme CAPE for a blizzard zeroing in on the US East Coast. What’s important to mention is that human-forced climate change has CAPE written all over it. Image source: Anthony Sagliani.)

In terms of the current storm, some of the CAPE potentials coming in are just off the charts. The above graphic, posted in this recent tweet by Anthony Sagliani, identifies the potential for 5 inch per hour thundersnow at Dulles International Airport (AID) between 2 AM and 2 PM Saturday. To be very clear, a 1 inch per hour snowfall was once considered an extreme event. Now we are looking at possibly 5!

A Record Hot Atlantic Feeds it All

In the context of human-driven climate change, this is one of the reasons why our warming up of the world can generate extreme weather. It warms the Earth unevenly. It puts cold next to hot by driving cold out of the polar zones and by warming up huge areas of land and ocean. And it dumps more moisture into the atmosphere through an amplified evaporation from these greatly warmed Earth surfaces. Mix it all together and you get Anthony Sagliani’s ‘tremendous vertical motion.’

How does this work? In two words — latent heat. More specifically the convective heat energy available in water vapor. And where does most of that latent heat energy come from? It comes, for the most part, in the form of warm waters evaporating into the air above the world’s oceans. More specifically to our current storm it comes in the form of record warm to near record warm temperatures in the waters of the Gulf Stream off the US East Coast (See Dr Jeff Master’s ‘The Future of Intense Winter Storms”).

(Sea surface temperatures off the US East Coast are more comparable to those seen during Summer than what would be typical for January. A 76 degree sea surface off Norfolk will provide a massive amount of heat and moisture to fuel the new kind of storm that is Jonas. Image source: Earth Nullschool.)

And they’re absolutely ridiculously warm — in the range of 76 degrees Fahrenheit in a region about 150 miles due east of Norfolk, Virginia. A region of ocean over which the developing storm center will directly cross. An area of water that is now in the range of 7 degrees Celsius above average (13 degrees Fahrenheit). For the ocean surface, this is screaming hot — more typical to summer than anything one would expect to see in January, even in the Gulf Stream.

You just don’t see these kinds of temperature departures for the ocean — or at least you didn’t before human-caused climate change started to ramp up. But now we have them — an ocean surface hot enough to support a hurricane but one that will this weekend provide fuel for a blizzard. So the kind of blizzard we will have will not at all be like even the usual blizzards of the 20th Century. This is the new, worse variety that will sadly become more frequent. Destructive, heavy snowfall in the 4-5 inches per hour range, thundersnow and storm surges combined, swaths of hundreds of miles impacted and crippled. The kind for the new age of a human-heated atmosphere — destabilized to produce freak storms of a ferocity and frequency the likes of which we have never seen.

UPDATE — Snowfall Begins With Some Models Showing 4 Feet or More Possible (Average Guidance For Gaithersburg is 24-30 Inches)

Wind and rates of snowfall have picked up somewhat over the past two hours. As of 3:42 PM, about 1-2 inches had fallen and the wind was visibly swaying some of the tree branches outside. Reports are coming in from regions to the south of a very heavy band of snow that should arrive in our area by later this evening.

Radar captures by the National Weather Service indicate this band setting up over much of Central and Eastern North Carolina — stretching northward through just west of Richmond. GFS model tracking and satellite confirmation indicate a coastal low developing in the region of Northern South Carolina. This low is beginning to transfer Atlantic moisture into the storm — pulling strong winds off that abnormally warm region of ocean just east of Norfolk and into the developing powerful snowfall band.

Sustained winds along the coast are now approaching gale force. We should expect these winds to rapidly increase over the afternoon and evening hours even as the moisture feed and rate of snowfall intensifies.

UPDATE: Rate of Snowfall Still Picking up at 6:05 PM; Heavy Bands Expected by 10 PM

Rates of snowfall continue to steadily increase for the Gaithersburg Area. As of 6:05 PM EST on Friday, 3-4 inches lay on the ground in Montgomery County Maryland. A heavy band of snow continued to gather to the south as the storm center went ongoing intensification near the border of South Carolina and North Carolina and just off-shore. Guidance provided by that National Weather Service indicates that heaviest rates of snowfall are still about 4 hours away. Radar indicates this band is forming just north of Richmond at this time.

UPDATE: At 10:30 PM, Heavy Snow Settles in with Six Inches Already on the Ground

As of 1030 PM, heavy bands of snow had started to stream into the Gaithersburg area. Winds were picking up — in the range of 15-25 mph with some higher gusts. A healthy covering of about six inches of snowfall already lay on the ground. National weather service radar at this time indicated a series of stronger bands of precipitation just south of DC and moving northward. Meanwhile, atmospheric analysis indicates the center of Jonas now over Eastern North Carolina and strengthening. Over the next 6-12 hours Jonas is expected to intensify as it traverses toward the Chesapeake Bay. This should bring increasingly intense bands of snowfall over the area.

By 1:35 AM, conditions again deteriorated for the region of Montgomery County. Snow accumulations had hit between 10 and 12 inches and the winds were really starting to howl and moan.

National Weather Service Radar indicated that the low pressure center had moved out over the Chesapeake Bay even as the wide-ranging storm really started to pull in substantial amounts of heat and moisture off the Atlantic. This kicked the storm into a higher intensity that will likely last, for the DC region, until around 1 PM tomorrow. We are entering the period of most intense storminess and snowfall now. Over the coming hours conditions could get quite extreme with 2-5 inch per hour snowfall rates and thundersnow in some areas. In other words — we’re starting to hit the height of this long-duration event.

National Weather Service Radar above shows very heavy snowfall bands moving directly over the DC Metro area at this time even as the Atlantic moisture feed grows more intense. Regional snowfall forecasts have remained quite extraordinary with most locations in the area now expecting between 18 and 40 inches. Still one heck of a night ahead!

This is not something that is normal for typically ice-choked Barrow, Alaska. Today, 25 to 35 mile per hour winds and fetch-driven, 10-15 foot high waves are breaking through coastal barriers and flooding the streets and homes of a town that is used to far more placid seas.

(Recently, Barrow city officials had a barrier of sand erected to protect structures from the newly ice liberated waters of the Beaufort Sea. Today, a strong coastal low pressure system’s surf smashed that barrier, flooded the coastal road, broke a channel through to an inland lake, and swamped numerous structures. Image source: Barrow Sea Ice Webcam.)

* * * * *

There’s been quite a lot of potential storm energy building in the Beaufort Sea this season. Nearby waters in the Chukchi have ranged between 3 and 5 degrees Celsius above average. Warmth, moisture and low pressure systems have flooded in from the Pacific off the back side of the Ridiculously Resilient Ridge to the south. It was a pool of warmth and heat just waiting for a trigger.

As August swung toward September, the near polar regions began to cool even as the Summer sun retreated. Temperature differentials between ice free sections of the Chukchi and Beaufort and remaining ice covered regions in the Central Arctic Basin hit new extremes. And, yesterday, a strong low pressure system began to develop off the Northern Alaskan coast (see video of yesterday’s building surf here).

(Fifteen foot waves north and west of Barrow, Alaska as detected by Earth Nullschool at 2:05 PM EST on August 27th. Image source: Earth Nullschool.)

In response, Alaska weather forecasters yesterday issued a High Surf Advisory. They probably should have issued a Coastal Flood Warning instead. For by today, the low had intensified to a 985 mb system. It has wrapped its left side in 35-45 mph winds and 10-15 foot seas. Seas that are now ripping large holes through coastal barriers erected to protect Barrow from a newly ice-liberated and storm-tossed Arctic Ocean.

High waves and surging seas are expected to persist, and possibly intensify, over the next 12-24 hours for Barrow. So currently observed coastal flooding may continue to worsen through tonight and tomorrow.

Coastlines Newly Vulnerable to Open Water Storms

The Northern Alaskan Coastlines, as with many Arctic shores, are used to typically placid or ice-locked waters. In the past, when sea ice dominated the Arctic Ocean during Summer, there were few open stretches of water available for a storm to generate fetch. Now, vast regions of Arctic Ocean remain open for long periods during July, August and September. In addition, with high amplitude waves in the Jet Stream delivering so much heat and moisture from more southerly regions, the late Summer and early Fall Arctic is increasingly primed for storms.

The result is strong storms running through open waters and generating powerful surf. Surf that is aimed at gently sloping beaches and low elevation coastlines with few natural barriers to protect against waves and storm surge. It’s a new vulnerability that today, for Barrow, resulted in a storm riled and ice free Arctic Ocean surging into streets, roadways and homes. Another climate change related situation that is new — if not at all normal.

A high amplitude ridge in the Jet Stream is forecast to develop atop the Yamal region of Russia, expand northward over the Kara and Laptev seas, inject a plume of anomalously warm air over the polar region, and then proceed on along the Arctic Ocean shores of Siberia. Beneath this ridge, temperatures over the Arctic Ocean will spike to +1 to +4 C above average while temperatures over land will hit extreme +20 C and higher anomalies.

(Arctic heatwave invades Siberia in the GFS forecast for later this week as depicted by Climate Reanalyzer.)

Arctic Ocean zones are forecast to see temperatures climb above freezing for much of the 80 degree North Latitude zone. Over Siberia, land-based temperatures are predicted to range from the 40s and 50s along the Arctic Ocean boundary and climb to the 60s to 80s in regions just inland.

As temperatures tend to flatten out over Arctic Ocean waters and as permafrost zones in Siberia are used to far cooler readings during Northern Hemisphere Summer, the predicted heatwave is likely to have some rather strong impacts should it emerge. Most notably, snow cover over remaining land and sea ice is expected to see a rather extreme reduction over the next seven days. In other words, GFS forecast models show Northern Hemisphere snow cover basically getting crushed:

Sparse remaining snow cover in Northeast Siberia along the East Siberian Arctic Shelf coastal zone is expected to be pretty much wiped out. One foot average snow cover along the shores of the Laptev and Kara seas is also expected to melt. And a broad section of remaining snow upon the sea ice is predicted to retreat away from the North Polar region — receding back toward the final haven near Greenland.

Snow is important for spring and summer-time Arctic temperature moderation due to the fact that it provides insulation to sea ice and permafrost as well as serving as a reflective, high-albedo surface that bounces back some of the incoming heat from the 24-hour seasonal Arctic sun. Snow melt, on the other hand, serves to form albedo-reducing melt ponds over the Arctic Ocean sea ice during summer. A critical factor in late season melt forecasting in which more June melt ponds tend to mean lower sea ice totals by end season. In addition, snow melt fills permafrost zone rivers with above-freezing waters that then flow into the Arctic Ocean — providing yet another heat forcing to the sea ice.

Conditions in Context

This weekly trend and forecast is consistent with an ongoing tendency during 2015 for strong ridge formation and warm air slot development over both Alaska and the Yamal region of Russia. The high amplitude ridges also likely have teleconnections with larger weather patterns such as El Nino in the Pacific, the warm water pool (hot blob) in the Northeast Pacific, and record low sea ice extents continuing for most of Northern Hemisphere Spring. Observations that are also consistent with the predictions made by Dr. Jennifer Francis that are a direct upshot of polar amplification set off by human-caused warming of the global climate system.

(GFS model forecast as depicted by Earth Nullschool showing ridge Northwest Territory, trough Greenland and North Atlantic, ridge Kara and Laptev region of Siberia. A dynamic that may be the result of teleconnections set off by factors related to human-caused climate change. Image source: Earth Nullschool.)

It’s worth noting that many of these factors are self reinforcing. For example, more sea ice melt results in higher amplitude wave formation in the Jet Stream. Higher amplitude wave formation in the Jet Stream transports more warmth to the Arctic environment, resulting in more sea ice and snow melt which in turn weakens the Jet Stream further. A longer-term amplifying feedback of Arctic carbon release may also be in play (hinted at by an overburden of both CO2 and methane in the local Arctic atmosphere), which would also contribute to the conditions we now observe.

A final feedback, this one somewhat negative, occurs as a result of Greenland Ice Sheet (GIS) melt. Large cold, freshwater outflows from GIS into the North Atlantic result in localized cooling in that region. This feedback (also related to AMO weakening) enhances trough formation throughout the North Atlantic region adjacent to Greenland and the Canadian Archipelago. A final potential teleconnection to the ridges we see forming over both Yamal and the Alaska/Northwest Territory zone.

Boston just experienced its snowiest month on record and, yes, it really is climate change, stupid. In essence, as Michael Mann notes above, it’s a matter of oceanic and atmospheric physics.

Consider the fact that the ocean surface is warming at an unprecedented rate. Consider also the fact that this observed warming is resulting in a number of powerful south to north flows of air over ocean regions and toward the polar zone.

Over the past month, these powerful warm air flows pushed strongly into both Alaska and Svalbard — causing 20-30 C above average temperatures in regions of the Arctic along the 70 to 80 degree north latitude lines. For Alaska, the warmth was so prevalent and intense that it forced the Iditerod sled dog race to be moved 300 miles north for want of snow and ice. On this past Sunday night in Svalbard, just above the 80 degree north latitude line, temperatures were a balmy 1.2 degrees Celsius. An extraordinary above freezing reading in a land where temperatures during this time of year are typically 20 to 30 degrees Celsius below that mark.

(Anomalous above freezing temperatures in the land of winter dark and chill. Also note the very powerful south to north air flows originating from the 30 degree north latitude line and terminating in the Arctic near 70 to 80 north. These flows exist in both the Pacific and the Atlantic — hugging the coastal zone and flowing strongly northward along a reoriented storm track. Image source: Earth Nullschool. Data source: Global Forecast System Model.)

All this warm air moving north must have an impact. And that impact is to leave Greenland and the eastern North American Continent as the remaining refuge for cold Arctic air that would typically amass over a rather thick pack of sea ice. But that sanctuary for cold is increasingly frail and unstable. For the ice is thinner and itself rests upon waters that are warming. So the cold instead moves to land and to land ice — both bodies with physical properties better able to keep cold during the long winter dark.

So the cold flees its previous habitat in the far north near the pole and instead dives about 1,500 miles south over Greenland, Eastern Canada and the US. In the upper atmosphere, this pattern is reflected by a huge trough in the Jet Stream. One that has been repeatedly identified by the crackerjack research of Dr. Jennifer Francis.

(Very high amplitude Jet Stream wave pattern with strong ridge in the west, very deep trough digging through Eastern Canada and the Eastern US, an a return to the strong ridge pattern over the North Atlantic. Image source: Earth Nullschool. Data source: Global Forecast System Model.)

Such a powerful hot-cold dipole in the atmosphere results in extraordinary atmospheric instability. The deep trough alone would be enough to send storm after storm hurtling toward the Northeast US. Storms born of a fury of Arctic cold coming into collision with oceanic moisture from the Gulf of Mexico and the Atlantic.

It is a pattern that has been fixed in place for a month running. One that has delivered storm after powerful storm to the US northeast along a screaming storm track. And one that has slammed these storms into an unprecedented wall of warmth and moisture.

For not only have warm air flows invaded the Arctic resulting in a highly anomalous displacement of cold air southward for an extended period of time. But ocean warmth in a region of the Atlantic just off Boston has provided extraordinary fuel for these storms once they arrive.

For we have observed sea surface temperatures just off Boston in the range of 8-11 C above average for most of the months of January and February:

For reference, a sea surface temperature anomaly of 2 C or higher is considered to be a rather strong departure. The 11.1 C anomaly in the above image is, for lack of a better term, simply off the charts. In rough translation, this amounts to surface waters in the range of 65 to 70 degrees Fahrenheit only about 200 miles or so off the Massachusetts coastline. A coastline regularly seeing temperatures in the range of 0-28 degrees F. The result is a 40-70 degree temperature departure over a very short distance. By itself, this extreme temperature differential would be an amazing storm generator. But the differential alone only tells half the story.

The other half is a powerful explosion of moisture off this much warmer than normal water. A massive mushrooming of moisture just off the coast. And when this very heavy bank of moisture collides directly with displaced onrush of cold and dry air, the amount of snow that is squeezed out can be staggering.

Record-breaking staggering. 8 feet for Boston in one month staggering.

As Michael Mann so saliently noted, you’d have to be a physics denier to not understand the role of ocean warming in either the warm air invasion of the Arctic in the Oceanic zones, the related displacement of cold air over the eastern half of the North American continent, or the fueling of extraordinarily powerful winter storms along the Northeastern Coast of the US.

It’s another day of Arctic Amplification — the fourth in an ongoing progression this week. Another day of extreme dipole temperature anomalies. And another day of record-setting weather. All symptoms, plain as day, of a world undergoing a fit of rapid, human-induced heating.

Warmth in The High Arctic Drives the Cold Out

Last night, while studying Earth Nullschool, I found a temperature of 27 F near Zemlya — an Island in the Arctic Ocean off Siberia. The night before last, I captured these two pictures — one of a region a few hundred miles south of the North Pole and well north of Svalbard at 22 F and another of the surface temperature near Richmond, Virginia at 20 F.

In other words, it was warmer just off Santa’s front porch than it was thousands of miles to the south in Richmond, VA.

In technical meteorological parlance there’s a term for such warm north, cold south temperature variations — dipole. In this case, it’s a cold North American Continent and a warm Atlantic Ocean pushing much higher than average temperatures far into the Arctic.

Jet Stream Re-Mangled — High Amplitude Jet Stream Waves

Such a warm airs surging north forcing cold airs south arrangement can result in some pretty extreme waviness in the Jet Stream. The kind of waviness that Dr. Jennifer Francis has warned is set off by just the kind of Arctic warming we witnessed this week.

And, as we can plainly see in the map below, we have an extraordinary meridional pattern in the Jet Stream occurring in perfect coordination with the current instance of polar heating:

I suppose some may call this kind of instance circumstantial. But what a circumstance, especially when one considers the plainly obvious and visible mechanism of the current polar temperature spike, the subsequent southward displacement of warm air from the polar zone, and the related warm air invasion flooding up from the North Atlantic into the heat compromised polar core.

It’s as easy to see as 1,2,3.

This re-arranging of air masses has re-instated the kind of circulation pattern around Greenland we warned about during late November of 2014. A kind of off-center displacement of air masses that shoves cold toward hot and can result in some rather extreme weather.

Record-Setting Winds over Scotland Last Night

Dr. Francis has also mentioned this resulting heightened severe weather potential in her research. And she can count herself among such visionaries as Dr. James Hansen who warned of ramping storm intensity resulting from a combined polar amplification and melting and softening of the remaining great glaciers in Greenland and, later, Antarctica.

Unfortunately, the more recent polar amplification episode did set off a spate of rather extreme weather in Scotland. The North Atlantic storm track intensified as temperature differentials ramped up. On Tuesday, a 930 mb low bombed out between Greenland and Iceland. Fed by a massive meridional air-flow, this storm soon generated very strong winds raging across the North Atlantic.

By last night, these winds roared throughout Scotland, peaking at 113 miles per hour — a new all-time record for the Northern Isles since wind measures began in 1970.

In a return to the kind of extreme weather that battered the UK for much of the winter of 2013-2014, trees were torn down, power lines unmoored and roads and railways blocked. This, in turn, forced a wide-scale emergency response throughout Scotland after last night’s brutal battering by hurricane force winds. From the BBC:

The storm caused the suspension of all ScotRail trains, although some limited services are now running. More than 46,000 homes are currently without power as the Atlantic jet stream caused gusts of more 100mph (160km/h).

So the observational evidence is pretty clear. Here we have yet another instance where polar heating is driving some rather extreme Jet Stream changes coupled with related instances of record extreme weather. And as human-related warming continues to intensify, we are likely to see far worse instances than today’s minor episode.

Last night, at around 9 PM Eastern Time, a broad region just south of the North Pole was undergoing an extraordinary warm-up. Temperatures along the 37 W Longitude line just 80 miles south of the pole had surged to 33 degrees Fahrenheit. A reading warmer than a region of central Michigan thousands of miles to the south but running over an area of sea ice more accustomed to -5 F or lower temperatures during the great dark of the December night.

(Knife of warm air drives above freezing temperatures to within 80 miles of the North Pole on December 1 of 2014. Image source: Earth Nullschool. Data Source: UCAR, OSCAR, NCEP.)

It was the much warmer than normal core of an intense and anomalous Arctic heat surge. One that blasted up over Svalbard and flooded into the high Arctic. Meeting with a similar but weaker air surge to the south, both surface and upper layers of the Arctic Ocean atmosphere hosted a joining of rivers of warm air.

This warm air double envelopment neatly sliced the polar vortex in twain. The remnant cold air cores at the Jet Stream level slipped down over both the Canadian Archipelago and Central Asia. Leaving open the lane for warm, maritime air to surge over the Arctic Ocean region.

(Jet Stream level atmospheric circulation shows polar vortex cut in two with one circulation over the Canadian Arctic Archipelago and the other over Yamal, Siberia — scene to the freakish methane blowholes earlier this year. Image source: Earth Nullschool. Data Source: UCAR, OSCAR, NCEP.)

It is a pattern of negative phase Arctic Oscillation (AO) — featuring a warming in the central Arctic which flushes the cold air out. But this ripping of the polar vortex in half is also related to polar amplification due to the human heat forcing. In which the high Arctic has warmed dramatically in comparison with the rest of the globe. So the heat anomalies we see now are much higher than they would otherwise be, with abnormal warmth remaining even into a positive phase of the AO (which we may see a bit more of, should El Nino finally emerge).

It’s a feature also related to a warming of the upper atmosphere at stratospheric levels. Such Sudden Stratospheric Warming (SSW) events can often be associated with the kind of polar vortex split we are seeing now. And, from recent observations, we find temperatures over the Arctic Stratosphere are now in record range.

Even though I wouldn’t categorize this as a *sudden* stratospheric event as of yet, the warming that has already occurred will likely have effects by middle December. In fact, the warming that has occurred is currently at record levels for this time of year.

For much of November, readings in the Arctic as a whole have ranged from +1.5 to +2.5 degrees Celsius above the global average. A region featuring the highest global anomalies in a world that just saw its hottest ten months in the past 136 years, and probably its hottest ten months in many thousands of years. A region well known for its cold — but warming far faster than almost anywhere else.

(The Arctic hits an extraordinary early December +3.16 C positive anomaly on the first day of the month amidst a flood of warm air from the Atlantic and Pacific Oceans. Image source: The University of Maine. Data Source: Global Forecast System Model.)

Today, beset by this abnormal heat, overall Arctic departures hit 3.16 C above the already hotter than normal 1979 to 2000 average. Regions within this warm zone showed readings well above 36 F higher than average. A kind of winter Arctic heatwave. One that will keep worsening as the human heat forcing continues its terrible advance.

Near Freezing Temperatures Over Zachariae Glacier During Meteorological Winter

Much of the added heat expanded through the region between the North Pole and Greenland, wrapping in a surface circulation that has tended more and more to envelop the frozen isle, Baffin Bay and the accompanying Canadian Archipelago.

This morning, some of that circulation and its entrapped warm air flow rode up over the East Coast of Greenland, surging over the ocean-facing cliffs of the Zachariae Glacier. Pushing temperatures to almost above freezing in a period where much deeper cold should be firmly established.

A great flood of abnormal winter warmth and moisture. The leading edge of a flow of ocean and atmospheric heat driven all too obviously by human warming.

In a normal world, during a normal late fall and winter, cold air would concentrate over a thick northern ice pack near the North Pole. The sea ice would be dense enough, unbroken enough, to lock a warmer ocean away beneath. The cold air core would be encircled by strong winds — both in the upper levels and at the surface. An atmospheric cold zone that would tend to be pretty steady, taking strong weather anomalies to drive it off a firm base of chill air.

In today’s world, the Arctic Ocean is warming. Connected to an also warming world ocean, the waters provide a launching platform for the added, human-driven heat. The surface sea ice is thus far thinner — containing less than 50 percent of the volume it boasted during the late 1970s. And, during this time of year, an extraordinary overburden of greenhouse gasses (primarily CO2 and Methane) continuously traps extra long wave heat radiation throughout the dark winter night.

All that extra heat gathering over the Arctic Ocean makes the cold air core far less stable. More and more frequently it is driven from its previous haunt near the North Pole. A climate change refugee looking for a cold air pool as temporary asylum from the inexorably building heat.

To the south, the still solid but increasingly endangered ice sheets of Greenland provide, perhaps, the most likely haven. So as the high Arctic heats up, the cold air re-centers over Greenland. And the result is a rather odd configuration in which atmospheric currents begin to displace southward, encircling Greenland rather than the polar regions. A disruption that results in a ripple of changes throughout the Northern Hemisphere — including serious alterations to the storm track and a far greater likelihood of the extreme weather producing planetary wave patterns.

Observational Support for Cutting-Edge Theories

The above described scenario draws from a number of cutting edge scientific theories. The first is Hansen’s Storms of My Grandchildren theory — in which a combination of polar amplification and enhanced Greenland melt drive severe changes to the Northern Hemisphere storm track, resulting in nightmarish weather. The second is the enhanced planetary wave theory, proffered by Dr. Jennifer Francis, in which Arctic warming drives severe changes and distentions in the Northern Hemisphere Jet Stream. The two theories are related in that Arctic warming, in both cases, is a primary driver of extraordinary climate and weather changes.

Thus far, we have seen growing evidence to support these theories, especially Dr. Francis’ theory, as ever since the mid 2000s we have observed an increasing prevalence of weak Jet Streams, strong planetary waves, and powerful meridional flows driving warm air into the polar zone, but also driving cold air out. Hansen’s Storms of My Grandchildren theory got a boost last year as a southward shifting cold air circulation ignited a powerful North Atlantic storm track that set off the roughest winter on record for England and the UK.

This year, we see similar weather phenomena related to these theories. The inundation of Buffalo with one year’s worth of snowfall in just two days was driven by a powerful planetary wave pattern directly associated with polar warming. A similar planetary wave is, today, threatening to dump more than a foot of snow across regions of the US Mid-Atlantic through New England. A January type winter storm on Thanksgiving that was preceded by 70 degree temperatures.

Not What Our Weather Models are Used to — The Greenland-Centered Cold Air Core

Today, we have yet one more pattern emerging that was predicted by these theories — polar air circulation centering around Greenland:

(Surface air flow encirclements of Greenland similar to conditions observed above were highly anomalous during the 20th Century. During the 21st Century, such a storm enhancing pattern is likely to become much more prevalent as an up-shot of human-driven polar warming. In the above shot, note the low spinning off Spain and heading toward Morocco off an anomalous and persistent dip in the Jet resulting from this abnormal pattern. More floods potentially on the way for that already hard-hit region. Image source: Earth Nullschool.)

In the above image, provided by Earth Nullschool and collecting data from US based global climate observations and models, we find warm air from the subtropical Atlantic being driven northward by first a mid-ocean high pressure system and then by a powerful low raging away off the southern tip of Greenland. The warm air flow rises north then joins with a continental flow rising off of Europe to cross the North Atlantic and the Barents Sea. Traveling along a cold frontal boundary sweeping out from Greenland, the warm air current surges up over Svalbard and toward the North Pole.

This warm air flow drives temperatures in a region within a couple hundred miles of the North Pole to 30.5 degrees Fahrenheit — warmer than current temperatures in central Pennsylvania and well over 36 degrees above average for this time of year in the far, far north:

(Svalbard and regions near the North Pole heat up as an extraordinary warm air wedge drives far, far north. Image source: Earth Nullschool.)

This extraordinarily warm air then becomes entrained in another low north of Greenland before following a polar air flow driving down over the Canadian Archipelago and Hudson Bay. A powerful north-south flow drawing over Baffin Bay into the strong low south of Greenland closes the loop. Thus we find Greenland encircled by winds, its cold air core far offset from the pole as the region over the Arctic Ocean warms.

As we can see in the surface wind map (top map), the surface air flow is running a complete circuit ’round Greenland. The result is that the cold air core driving NH atmospheric circulation at the surface is now centered over Greenland and Baffin Bay. It is displaced many hundreds of miles south of the North Pole. And the North Pole itself has become over-run by a warm air flow at the periphery of the cold air circulation’s center.

Upper level wind patterns are similarly disrupted with a cold upper air low churning away over Baffin Bay and a second cold core circulating over Central Siberia. In both cases, in the upper levels near the Jet and at the surface, the region of the Arctic Ocean is disassociated from the cold air centers and related atmospheric circulation. A set of conditions that has come to very well resemble those predicted by Dr. Francis, or worse, look more like a precursor to Hansen’s Storms of My Grandchildren scenario.

In this case, for today, the weather observations match the warming-induced pattern just as predicted.

Mainstream meteorologists, including those at the Weather Channel, continue to cover current weather as if it is occurring under traditional conditions while only providing sideways references to cutting edge science related to observed atmospheric warming. A new subset of the science that provides much greater insight into what may actually be happening and is a very useful tool for weather prediction in the currently altered and radically changing climate state.

Like geologists who failed to take into account for plate tectonics theory in the mid 20th Century, meteorologists adhering to old weather prediction methods risk becoming outmoded and less relevant to current, and rapidly evolving, climate realities. The new global warming science both bears out in the observational data and in its usefulness to predict extreme events — so, for the sake of accuracy, it needs to be included.

According to GFS model runs and observational data, the past 24 hour period has shown temperatures in the range of +0.72 C above the already hotter than normal 1979 to 2000 average. A hot day in a hot month that is likely to be among the hottest on record, if not an all-time record-breaker itself.

A couple of days ago, hourly CO2 levels rocketed from 396 ppm to 399.5 ppm. A rather odd and somewhat ominous jump back toward the 400 ppm level at a time of year when atmospheric CO2 should be just starting a slow rebound from lowest ebb. A bottom that this year hit about 395 ppm during mid September. A measure already more than 2.2 ppm above last year’s low. To say the least, an hourly upward swing of 3.5 ppm isn’t exactly normal, especially when one considers the fact that the world hasn’t seen near 400 ppm CO2 levels for about three million years (this year peaked near 403 ppm during late spring).

And all that extra CO2, when combined with other greenhouse gasses, is having an increasingly obvious impact on climate. We see it in the record global average temperatures. We see it in the rising oceans which have come more and more to threaten the cities, lands and isles upon which so many of us reside. We see it in increasing instances of extreme weather around the globe — in the extraordinary and often persistent droughts, floods, storms and wildfires. And we see it in the form of a rather strong temperature amplification at both poles.

(Global temperature anomaly maps provided by GFS and the University of Maine shows no regions of the world cooler than average with the highest abnormal warm temperature departures concentrated, as usual, at the poles.)

Greenhouse Gasses as Primary Driver of Polar Amplification

Today, the Arctic is 1.60 C above the already hotter than normal 1979 to 2000 average. Meanwhile, the Antarctic boasts the highest departures for any global region at +2.09 C. Taking a closer look at the Antarctic Continent, we find an angry red splotch featuring temperature anomalies in the range of +12 to +20 C above average. A region associated with a tropics-to-pole transfer of airs we’ll discuss more in depth later.

What causes such a powerful and visible polar amplification? In short, it can best be described as the general impact of added greenhouse gasses on the global climate system.

Because most of the sun’s radiation falls on the equatorial regions, temperatures there are governed to a greater degree by direct solar insolation. But move toward the poles where sunlight hits the earth at a much lower angle, if at all, then the impact of the greenhouse effect holds greater sway. There, the ability of a gas like CO2 to trap and re-radiate long wave solar heat radiation can have a rather extraordinary impact.

On an Earth with no atmosphere, the temperature differential between poles and equator, between night and day, would be even more extreme than the variance we see today. But as the atmosphere thickens and the greenhouse gas overburden intensifies, the temperature difference grows less. For Earth’s present climate the temperature difference between the Equator and the Arctic averages about 42 degrees C. For the Antarctic, the average is about 71 degrees C.

On a world like Venus, where a kind of super greenhouse is in force and much of the atmosphere is composed of CO2, there is practically no difference in temperature between the equator and the poles. The reason for this is that greenhouse gasses trap the sun’s long wave radiation and recirculate it around a planetary system. And on Venus, a ray of long wave sunlight that comes in has very little chance to get out. So its heat recirculates many times within Venus’s atmosphere before it finally escapes.

On a place like Earth, where greenhouse gas levels are increasing, we would expect the temperature difference between the equator and the poles to drop as the poles warm faster due to the added impact of the increased greenhouse gasses. And since about the mid 20th Century, this is exactly what we’ve seen.

(Top frame shows North Pole to Equator temperature difference since 1948. Bottom frame shows South Pole to Equator temperature difference from 1948 to 2011. Note the approximate 3 C temperature swing indicating a faster warming at the poles in both graphs. Data is from the NCAR-NCEP reanalysis model.)

Lowering differences in Equator to polar temperature on a warming world also denotes a much faster warming of the polar zones. Hence the term polar amplification.

Now, for the Arctic, polar amplification has also become synonymous with loss of sea ice, loss of snow cover, increased land darkening due to changes in vegetation, and local release of greenhouse gasses via feedbacks from the Arctic environment. Each of these changes has the potential to add increased warming on top of the warming already being driven by global greenhouse gas increase even as such changes likely also drive changes to local and Northern Hemisphere weather. But as important as these additional changes may be, the larger driver remains an increase in global greenhouse gases driven by human emissions.

How Polar Amplification Drives Changes to the Jet Stream

In the end, such a polar amplification is a strong driver for changes to the world’s weather. Primarily, by reducing the difference in temperature between the poles and the Equator, we tend to see weaknesses forming in the circumpolar wind field known as the Jet Stream. At times, the Jet will slow and meander, allowing for the formation of ridges that extend far into polar zones and for troughs that dip deep into the middle and lower latitudes. Rather than a west-to-east flow of wind and weather, such a shift generates more of an Equator-to-pole flow:

And today we see two large north to south flows issuing from the 20 degree south latitude region, traversing thousands of miles of ocean in a poleward flood and terminating at the great ice sheets of Antarctica in the region of 70 to 75 south latitude.

Note that the flow originating off the west coast of South America terminates at the vulnerable West Antarctic Ice Sheet — a region that has been warming at an extraordinary pace of 0.25 to 0.5 C each decade. The second flow, originating from the South Atlantic and terminating over East Antarctica is heavily involved in the +12-20 degree C temperature anomalies ongoing there today.

Looking at these massive flows of air and the related spikes in temperature anomalies, it is easy to become confused over the issue of cause and effect. But it is simple to recall if you understand that first, added greenhouse gasses warmed the pole which in turn weakened the Jet Stream, which in turn allowed an amplification of the north-south meridional flow transporting yet more heat into this southern polar region.

For the southern polar region, today, we see some extraordinary high temperature departures for mid-to-late spring. At this time, polar amplification should be fading as more sunlight streams in. And yet we have a still strong positive temperature anomaly.

And as for the northern polar zone with its numerous additional polar amplification vectors, we shall see to what degree, if any, a potentially emerging El Nino tamps down the extraordinary meridional flows and polar vortex disruptions seen during just this past year’s freakish winter of 2013-2014.

(Sao Paulo region of Eastern Brazil clearly visible through a mostly cloudless but smoke-filled satellite shot on October 15. Note both the dessicated, browned land of a normally green region together with the steely gray smoke funneling in from wildfires both near Sao Paulo and further north in the drying Amazon rainforest. Intense heat and lack of rainfall combines with fires to create a pallor of smog over much of Brazil also visible here. Image source: LANCE-MODIS.)

For a Europe facing off against an Atlantic and Arctic undergoing these wrenching changes, the story is altogether related. Sections of Southern France over a recent six week period received enough rain for an entire year. The Mediterranean waters off this region had heated to between 3 and 4 C above average dumping an intense load of moisture into a hungry upper level low that delivered storm after storm to the beleaguered regions. One spate of deluge dumped a full six months of water from the skies in just three hours.

(Monster storm that bombed out to 952 mb on Wednesday lashes the UK and Ireland with rain and gales on Friday and Hurricane Gonzalo threatens Bermuda. Gonzalo is set to make an eastward turn across the Atlantic and will possibly impact the UK as a tropical storm by Monday or Tuesday of next week. Image source: LANCE-MODIS.)

The current storm is expected to rake through the UK and Ireland throughout this weekend before fading off toward the north. As it lifts, hurricane Gonzalo — now packing 125 mph winds and threatening Bermuda — is forecast to surge into the UK with tropical storm intensity come Monday or Tuesday of next week.

The 1-2 punch is reminiscent of a relentless series of storms that battered the UK this past winter. A sequence spurred by extraordinary and unprecedented changes to the North Atlantic climate including a slowing of the Gulf Stream, a powerful warming of surface waters in the Arctic, major losses to sea ice in almost all Arctic seas, and increasing cold, fresh water outflows from Greenland. The net effect is to enhance storm track intensity across the Atlantic as warmer waters and airs surge northward coming increasingly into contact with cold polar air and generating powerful and intense storms during the winter, fall, and spring seasons.

With global temperatures flirting with new record highs and with El Nino possibly flaring to life in the Pacific, the end of 2014 and the start to 2015 is altogether likely to see a continuation of such intense, extreme weather. Weather that is severe enough to cause damage and disruption in some areas or even powerful enough to throw whole cities and regions into instability.

Just a few of the tragic results of a warming climate as we approach the 1 C above 1880s temperatures mark.

(Winds flowing north from just west of Hawaii, through the Bering Strait, over the North Pole and on into the North Atlantic as seen by NOAA’s GFS model and imaged by Earth Nullschool.)

This is a very odd pattern for global surface winds.

In the central Pacific, along a band above 20 North Latitude and about 500 miles west of Hawaii, a broad stream of easterly winds yesterday took a turn toward the north. The wind field was then pulled into a long frontal boundary spinning out from a large low pressure system off Irkutsk, Russian and driven on toward the Western Aleutian Island Chain.

The winds continued their sprint northward through the Bering Strait before being again captured by a low, this time over the East Siberian Sea. Sped on by this second nudge, the winds, running at 15-25 mph, spilled over the North Pole and into a third low spinning just north of Svalbard. This system shoved the winds southward over the North Atlantic and finally into a cyclone just north of England where the winds finally turned eastward, returning to the prevailing west-east global flow.

This is an epic journey in defiance of typical and prevailing weather patterns spanning thousands of miles and three oceans. It is decidedly not normal.

A Ruptured Jet Stream and A Flood of Winds Across the Pole

Typically, cold air over the polar region will insulate the Arctic from these kinds of circumpolar flows. The cold air to the north, warm air to the south, drives winds faster around the pole, creating a kind of wind wall that keeps south-north flows out of the Arctic. It is a pattern that tends to isolate Arctic air from the rest of the global air circulation to the south.

(Mostly disassociated Jet Stream with large rupture running north through the Bering Strait and on over the polar zone. Image source: University of Maine.)

But, during recent years, temperatures in the far north have been rapidly rising by in some cases as much as 0.5 to 1.0 degrees Celsius per decade. This heating of the polar zone, together with land and sea ice loss, has resulted in a weakening of the circumpolar wind pattern called the Jet Stream. This weakening has collapsed the wall keeping southerly winds from rushing over the Arctic as we see today.

The current pattern involves an extreme weakness and high amplitude wave in the Jet Stream extending from the Central Pacific and into the Arctic, extending well above the 80 degree North Latitude line. What remains of the cold air pool has been split, with some of the cold air mass shoved toward Greenland and the Canadian Archipelago and the remainder shoved toward the Kara Sea. Driving through it all is a wedge of warmer air accompanied with the southerly winds, winds that originated in the tropics near Hawaii.

For the Northwest Territory of Canada, the story this summer has been one of record-setting wildfires. Fires casting away smoke plumes the size of thunderstorms, fires that burn regions of tundra the size of small states. Fires that just burn and burn and burn for weeks on end.

But to the south and east in Saskatchewan and Manitoba, the story is drastically different. For over the past month, unprecedented flooding in this region has wrecked untold damage to Canada’s farmlands.

(Powerful storms over Manitoba and Saskatchewan on July 23rd, 2014. Image source: LANCE-MODIS)

This situation is the result of an odd and wreckage-inducing tangle in the Jet Stream. For hot air has been funneling up over the Northwest Territory for the better part of two months now, pushing temperatures in this Arctic region into an unprecedented range topping the 70s, 80s, and even 90s on some days. This high amplitude ridge in the Jet Stream has been reinforced and locked in place, a result some scientists attribute to the loss of Arctic sea ice during recent years, setting up a hot weather pattern favorable to wildfires.

As the massive Arctic wildfires ignited and burned, they cast off giant streams of smoke, burdening the down-wind atmosphere with aerosol particles — an abundance of condensation nuclei for cloud formation. These smoke streams fell into a trough flowing down over Manitoba and Saskatchewan. The deep trough, often extending far into the Central US formed a kind of trap for storms and, like the fixed ridge over the Northwest Territory, it has remained in place for months on end.

Given this mangled positioning of atmospheric heat and moisture flows, it was only a matter of time before massive rainstorms erupted in the wake of the large-scale Canadian fires. And the result was an unprecedented flooding. The offspring of an unprecedentedly powerful and persistent atmospheric pattern set off by human warming.

Major Floods Wreck Canadian Crops

For some local farmers, the past couple of days have seen 48 hour rain totals in excess of 10 inches. A 100 year rain event at a scale few farmers in the region have ever seen. And the recent floods are just the latest in a series of heavy rainfalls that have been ongoing ever since early July. Flood follows flood follows flood. A progression that has left most farms swimming in inches to feet of water and mud.

In total, farmland encompassing 3 million acres in Saskatchewan and 2.5 million acres in Manitoba are now under water and are unlikely to produce any crops this year. As a result, wheat plantings are expected to decline by 9.8 percent from last year, canola is expected to decline by 5.8 percent from the June forecast, and oat is expected to decline by 6 percent, according to estimates from Bloomberg.

July flooding in these regions has so far resulted in over 1 billion dollars in damages to farmers. As much as half of these losses may not be covered as insurers are still reeling from severe moisture damages during 2011, just two years ago. As a result of the ongoing parade of storm casualties, insurers have also raised deductibles, leaving farmers more vulnerable to the odd and powerful new weather coming down the pipe.

The Part Played By Climate Change and a Mangled Jet Stream

We often hear of the expanding droughts of human-caused climate change wrecking croplands. But the upshot of expanding drought in one region is record downpours in another. And downpours, if they are intense enough, can have a negative impact on crops as well.

(High amplitude Jet Stream wave pattern fueling wildfires in the Northwest Territory and record floods in Manitoba and Saskatchewan. Note the extreme northward projection of the Jet over the Northwest Territory and the strong, deep, trough back-flowing from Hudson Bay into Manitoba, Saskatchewan and the northern tier of the Central US. Image source: University of Maine.)

One mechanism that has tended to amplify drought and rain events during recent years has been a weakening and intensifying waviness of the Northern Hemisphere Jet Stream. This weakening has been attributed by some scientists to a large-scale recession of Arctic snow cover and sea ice. For since 2007, not one day has seen an average sea ice extent and the range has typically fallen into a zone between 20-50 percent below levels seen during the 1970s and 1980s. New major record low years in 2007 and 2012 have also fueled speculation that sea ice may completely melt away during one summer between now and 2030, 2025, or even 2020 — 50-100 years ahead of model predictions.

As the sea ice serves as a haven for cold air masses, its loss is bound to impact the resiliency of these systems and since a solid pool of cold air to the north is a major driver of Northern Hemisphere upper air currents, the weakening of this cold pool has had dramatic impacts on climates.

(Extreme dipole hot/cold pattern associated with Jet Stream mangled by climate change. Image is for July 14, a match to the above Jet Stream shot. Note the extreme heat in the ridge and the much cooler air in the trough. This is exactly the kind of pattern we would associate with sea ice retreat and Jet Stream weakening. Image source: University of Maine)

For this year, the ridge over Canada’s Northwest territory was a direct upshot in a northward retreat of the Jet Stream over Canada and, at times, into the Arctic Ocean. This set the stage for severe wildfires in the zone of warmth underneath this ridge pattern. To the east, a powerful downsloping trough pulled cooler air into Saskatchewan and Manitoba as well as over the Central and Eastern US. This set the pattern up for cooler than average conditions as well as for strong rainstorms.

The crop-shattering events of July were a direct result of this climate change induced ‘Song of Flood and Fire.’ A pattern we’ve seen repeat again and again over the past few years and one that may well intensify as both time and human-caused warming advance.

To the west, a heat dome high pressure system sits its dry and desiccating watch, deflecting storm systems northward toward Canada, Alaska, and, recently, even the Arctic Ocean. It is a weather system that drinks deep of Northwestern Pacific waters heated to 2-4+ C above average by humankind’s extraordinary greenhouse gas overburden. A mountain of dense and far hotter than normal air that is shoving the storm-laden Jet Stream at a right angle away from the US west coast and on up into an Arctic Ocean unprepared for the delivery of such a high intensity heat and moisture flow.

(Not one, not two, but three high pressure centers stacking up on June 24, 2014 off the North American West Coast. The highs are indicated by the white, clockwise swirls on this GFS surface graphic. This triple barrel high pressure heat dome represents an impenetrable barrier to storms moving across the Pacific Ocean. You can see one of these storms, represented by the purple, counter-clockwise swirl approaching Alaska and the Aleutians. A second Pacific-originating storm is visible north of Barrow in the Beaufort Sea. Under a typical pattern, these storms would have funneled into the US west coast or skirted the Alaskan Coast before riding into Canada. Storms taking a sharp left turn through Alaska and the Bering Sea into the Arctic is an unprecedented and highly atypical weather pattern. Image source: Earth Nullschool. Data Source: NOAA/GFS.)

What do the west coast blocking pattern, the California Drought, the Mackenzie Delta Arctic heatwave and the Savannah summer shower turned monster storm have in common? Twelve words: hydrological cycle and jet stream patterns wrecked by human caused atmospheric warming.

Three Year Long Drought Intensifies

Californians, at this time, may well be hoping hard for a mutant summer shower like the one that hit Savannah yesterday. But they won’t be getting it anytime soon. The triple barrel high off the US west coast won’t move or let the rains in until something more powerful comes along to knock it out of the way. And the only hope for such an event might come in the form of a monster El Nino this winter. Then, Californians may beg for the rain to stop. But, for now, they’re digging in their heels to fight the most intense drought in at least a hundred years.

(This week’s California Drought Map provided by the US Drought Monitor. Orange indicates severe drought, red indicates extreme drought, and that brick color spreading from the coast and into California’s Central Valley is what they call exceptional drought. Not a corner of the state is spared severe or higher drought levels, with fully 77% of the state suffering from extreme or exceptional drought.)

With no rain in sight, with the snows all gone from the Sierra Nevada mountains to the east, and with both federal and state reservoirs under increasingly more stringent water restrictions, what it means for Californians is incessant drilling. So far this year an estimated 450 million dollars has been spent statewide to plunge ever-deeper wells into the state’s rapidly-dwindling underground aquifers. In regions where a 200 foot well was once considered deep, 600, 800 or even 1000 foot wells are now common.

In total, about 75% of California’s lost water supply has been replaced by what essentially amounts to mining ground water. But the drought mitigating flow can only last for so long. And if the rains don’t come, those sources will first dwindle and then dry up. So California’s agriculture and a decent chunk of its other industry may well be living on borrowed time facilitated by unsustainable drilling for water.

“I’m in a community out there with about 20 homes. We’re on one deep well ourselves and we lost it two years ago. We were at 200 feet and now we are down to 400 but all these new guys are going down to six, 800 and 1000 feet; it’s going to suck us dry here again pretty soon.”

So for Central Valley residents it’s literally a race to the bottom in the form of who can dig the deepest well the fastest.

(Sierra Nevada Mountains in right center frame shows near zero snow cover on June 24 of 2014. Typically, California relies on snow melt to stave off water shortages through dry summers. This year, with drought conditions extending into a third year, snow melt had dwindled to a trickle by mid June. Sattelite Imagery provided by NASA LANCE MODIS.)

Global Warming to Raise Food Prices

For years, scientific models had shown that the US Southwest was vulnerable to increased drought under human-caused warming. Scientists warned that increased community resiliency combined with rapid reductions in global carbon emissions would be necessary to preserve the productiveness of regions vital to the nation.

California is one such region. Its economy, even outside the greater US, is the 8th richest in the world. It is also the US’s largest producer of vegetables, most fruits, and nuts. Other major agricultural production for the state includes meat, fish, and dairy.

Though much of the current drought’s impacts have been mitigated through unsustainable drilling for ground water, US meat and produce prices are expected to rise by another 3-6% due to impacts from the ongoing and intensifying California drought. But so far, major impacts due to large-scale reductions in total acres planted have been avoided. Without the drilling, overall repercussions would have been devastating, as planted areas rapidly dwindled in size. But with wells running dry, time appears to be running out.

(Mangled Jet Stream on June 20th, 2014 together with cut-off upper air low threatens record-shattering storms and flood events across a multi-state region from the Dakotas to Minnesota to Iowa and Nebraska over the coming days. Image source: Earth Nullschool. Data source: NOAA.)

If you wanted an example of a Jet Stream mangled by human-caused climate change, you couldn’t find a better one than today’s tangle of upper level winds swirling over North America.

It’s a chaotic maelstrom of split flows, colliding storm tracks, blocking highs, and cut-off upper air lows. A barrel of snakes pattern that’s become ever-more-common since Arctic sea ice plummeted to staggering volume lows of nearly 80 percent less than 1979 levels at end summer of 2012. A loss that opened wide the gates for warm air to flood northward and confuse the hot-cold dividing line that drives this key weather governor.

Over the past week, we’ve seen what amounts to a mess of storms mostly locked in place. A Pacific Ocean flow squeezed between a blocking high off California and an upper level low south of Alaska drew a train of moisture trailing all the way across the Pacific into a hungry cut-off low that had stalled along the border between Canada and the US. Drifting slowly east to west, west to east, the low gorged on the synoptic moisture feed, dumping record rainfall after record rainfall over the Dakotas, Minnesota, Nebraska and Iowa.

(Record flooding along the Big Sioux River in Iowa and South Dakota as witnessed yesterday by Storm Chasers.)

All the massive rainfall has built up quite a pulse of flood water that is now moving down major river systems and threatens record flooding events throughout a multi-state region from the Dakotas to Minnesota to Iowa to Nebraska. Residents are being called to aid in sand bagging and other flood mitigation operations as rivers keep rising through numerous regions. According to a report today in the Christian Science Monitor:

“In Iowa, South Dakota, and Nebraska, officials are asking volunteers to build sandbag barriers and other fortifications in advance of the brunt of the storm – but politicians and emergency workers are conceding that their efforts, in some areas, may not be enough.

In South Dakota, workers have begun turning a major Interstate exchange bridge into a temporary levee. While officials there say that will mitigate the flood in many locales, Governor Dennis Daugaard (R) said he expects parts of North Sioux City, S.D., to be underwater by the end of the week.”

Storms Expected to Continue

Today a frontal boundary sweeping out from our upper air low is bringing rains to the Great Lakes and Central Plains region. Meanwhile, behind the front, instability and moisture flow beneath the low continue to result is a high risk for severe thunderstorms accompanied by strong winds, torrential downpours, hail and frequent lightning. Severe storm risks are most extreme for areas of southeastern Nebraska, western Iowa, northern and western Minnesota, and eastern North Dakota.

Already, satellite imagery shows strong storms and accompanying high cloud tops popping up over Nebraska with more likely to follow as afternoon and evening progresses.

Conditions in Context: How Climate Change Intensifies Droughts/Storms

Multiple news agencies are now gathering reports of record storm events throughout the affected multi-state region. Recording agencies and residents alike note a dramatic increase in both the frequency of record events and in their intensity.

Storm precipitation intensity is a measure of how much rain, snow, sleet or hail falls from a given storm over a given period. And what we have seen is an increasing number of record hourly rainfall events in which precipitation totals measure 1 to 2 inches or more within a 60 minute span. Such intense events rapidly overwhelm infrastructure, flood roads, and burst river banks, creating a dangerous situation that often results in numerous water rescues. And both local and national climate reports have marked a major increase in both precipitation and precipitation intensity over the past two decades for regions such as Iowa.

In the context of human-caused climate change, frequency of intense storm events is increased due to rising atmospheric moisture loading. Overall, for each 1 degree C increase in temperature, the hydrological cycle increases by about 7% in intensity. The current .8 C rise since 1880 has resulted in about a 6% increase in the rate of evaporation and of rainfall. So in regions where heat and dryness tend to take hold, the soils tend to dry out faster, tipping into drought conditions far more rapidly and seeing an overall intensification and lengthening of droughts. And in regions where storms do form, they tend to dump far more rainfall than they used to.

Changes in the Jet Stream due to loss of sea ice in the Northern Hemisphere also tends to result in more persistent weather patterns. The Jet Stream tends to meander more, spinning off more cut off lows that linger over regions creating instability and rough weather for longer periods. High amplitude waves tend to also form as more warm air invades the higher Latitudes. In the ridges, powerful high pressures tend to dominate. And once these highs establish, they can be very difficult to move. Beneath these blocking highs, droughts proliferate due to the extreme length of dry periods and due to the intensified rate of evaporation. We see such an event now in the 15+ month long blocking high that has so greatly impacted California and the ongoing drought there.

Lastly, increasing convection and a thickening, hotter atmosphere tend to spike storm intensity. In areas where moisture and heat are both high, the explosive rate of evaporation tends to rapidly form storms with very high cloud tops. These cloud tops, now sometimes pushing 50,000 or 60,000 feet pack in more moisture and can generate very intense rainfall events over shorter periods than we are used to.

In these ways, climate change forms an ideal brew for perfect thunderstorms and perfect droughts. With temperatures expected to spike to +2 C or great anomalies over the coming century, we can look forward to extreme weather continuing to intensify with both record rainfalls and record droughts dominating with ever-increasing frequency.

Black, ominous clouds have been dumping heavy rainfall over southeast China ever since May 12.

Warm winds, laden with the moisture spilling off a super-heated Pacific Ocean, collided with an intense storm track that often combined upper level moisture flows spilling off the heat dome near the Caspian, a high intensity heat and evaporation event now ongoing over India, and cold, unstable air streaming down from the Kara Sea in the Arctic. Since mid-May this relentlessly persistent pattern has been in effect. And the inundation has been ongoing and extraordinarily intense with day-after-day deluges pounding a sprawling region from south-central China and on to the coast.

(Chinese news report from yesterday showing widespread flooding.)

Each new dawn brings with it fresh losses with numerous major roads closed, bridges washed out, and adding to what is now an almost endless tally of evacuation orders. Daily rainfall totals in the range of 2-6 inches or more have saturated grounds, burst riverbanks, and turned streets into torrents. By today, more than 1 million people had been impacted with nearly a half million evacuated or rescued from flooded buildings. Since the, still ongoing, floods began in mid-May, more than 25,000 homes and 40 souls have been lost to the epic storms.

(Relentless heavy rainfall over Southeast China visible in the above four satellite images on [left to right, top to bottom] May 12, May 18, May 23rd and May 27th. Image source: LANCE-MODIS.)

The Chinese have invested heavily in flood defenses since the 1998 deluge that resulted in 4,000 dead, over 15 million homeless, and 26 billion dollars in damages. During that year, a strong El Nino set off severe storms that turned large Chinese rivers into raging inland seas. The Three Gorges Dam on the Yangtze was built, in part, to prevent this kind of terrible flooding.

But fears of a possible repeat of the 1998 event are on the rise despite heightened Chinese defenses. A strong El Nino may again be gathering in the Pacific and with global temperatures now warmer than even those seen during the late 1990s, atmospheric moisture loading is probably at its highest in at least the last 10,000 years.

High atmospheric heat content increases both the frequency of severe rain and drought events due to an amplification of the hydrological cycle through evaporation. Overall, it is estimated that the current .8 C of warming over 1880s temperature averages has caused a 6% amplification of the hydrological cycle worldwide. That’s 6% heavier rainfall and 6% more intense droughts when averaged over the entire globe. But as we well know, weather isn’t an evenly distributed phenomena. Some regions are more likely to receive a bulk of that increased rainfall even as others are more prone to see a majority of the increased drying. Add to this consequence a meandering Jet Stream (set off by loss of Northern Hemisphere sea ice) with the tendency to lock in very persistent weather patterns and you end up with a greatly enhanced likelihood for extreme weather due to the wide-ranging effects of atmospheric warming.

Weather Forecast Calls for More Severe Storms

For southeast China, weather patterns will remain locked in for a continuation of potential extreme rainfall over the next week. The large heat domes over the Caspian and India will continue to spill out moisture over Southeast China even as the extraordinarily warm Pacific provides its own moisture flow. Notably, the weather forecast for this Wednesday calls for another large outbreak of thunderstorms with the potential to drop 2-4+ inches of rainfall over already saturated and inundated grounds. Thursday through Sunday is expected to bring yet more waves of severe thunderstorms to the region.

Given this combined extreme weather and climate state it is certainly possible that the current flood tally will continue to lengthen for Southeast China.